Radiation Hardened Bandgap References

Abstract

As a key component in the proposed multistage noise-shaping (MASH) $\Delta\Sigma$ time-to-digital converter (TDC) system, the total ionizing dose (TID) radiation tolerance of the bandgap reference in deep-submicron -complementary metal–oxide–semiconductor (CMOS) technology is generally limited by the radiation-introduced leakage current in diodes. An analysis of this phenomenon is given in this book, and a dynamic base leakage compensation (DBLC) technique is proposed to improve the radiation hardness of a bandgap reference built in a standard 0.13 μm CMOS technology. A temperature coefficient (TC) of 15 ppm/°C from -40 to 125 °C is measured before irradiation. The voltage variation from 0 to 100 °C is only ± 1 mV for an output voltage of 600 mV. Gamma irradiation assessment proves that the bandgap reference is tolerant to a total ionizing dose of at least 4.5 MGy. The output reference voltage exhibits a variation of less than 3 $\%$ during the entire experiment, when the chip is irradiated by gamma ray at a dose rate of 27 kGy/h.